Realizing Ultrahigh Detectivity and Fast Respond Speed Self-Powered Photodetectors Based on PdSe₂/Gr/InSe van der...

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Two-dimensional (2D) semiconductor materials are crucial for next-generation microelectronics.
• 2D van der Waals heterojunctions offer potential for self-powered photodetection.
• Interface quality significantly impacts device performance, necessitating atomic-scale control.

Purpose of the Study:

• To design and fabricate a high-performance self-powered photodetector using a 2D van der Waals heterostructure.
• To investigate the effect of a graphene interlayer on device performance.
• To demonstrate the application of the photodetector in an imaging system.

Main Methods:

• Fabrication of a PdSe2/Gr/InSe 2D van der Waals heterostructure photodetector with a graphene interlayer.
• Characterization of the device's photoelectric performance across a wide spectral range (405-980 nm).
• Evaluation of response speed, detectivity, responsivity, and light on/off ratio.

Main Results:

• The photodetector demonstrated excellent self-powered photoelectric performance.
• Achieved high responsivity (937.6 mA/W) and detectivity (4.6 × 10^12 Jones).
• Exhibited a fast response speed (34/39 μs) and a high light on/off ratio (6.99 × 10^5).

Conclusions:

• Inserting a graphene interlayer effectively improves interface quality in 2D heterostructures.
• The developed photodetector shows significant potential for high-performance, fast-response optoelectronic devices.
• The study introduces an effective strategy for fabricating advanced photodetectors.